ValueError when copying a product with custom attributes

[arthru]

When copying a product that have custom attributes, openerp tries to also copy its group leading to this stack :

Uncaught exception
Traceback (most recent call last):
  File "/home/openerp/openobject-server-7.0/openerp/osv/osv.py", line 131, in wrapper
    return f(self, dbname, *args, **kwargs)
  File "/home/openerp/openobject-server-7.0/openerp/osv/osv.py", line 197, in execute
    res = self.execute_cr(cr, uid, obj, method, *args, **kw)
  File "/home/openerp/openobject-server-7.0/openerp/osv/osv.py", line 185, in execute_cr
    return getattr(object, method)(cr, uid, *args, **kw)
  File "/home/openerp/branch_bzr/prestashoperpconnect/prestashoperpconnect/product.py", line 278, in copy
    context=context)
  File "/home/openerp/openobject-addons-7.0/mrp/product.py", line 37, in copy
    return super(product_product, self).copy(cr, uid, id, default, context=context)
  File "/home/openerp/branch_bzr/openerp-product-attributes/product_images/product.py", line 52, in copy
    return super(product_product, self).copy(cr, uid, id, default, context=context)
  File "/home/openerp/branch_bzr/openerp-product-attributes/product_sequence/product_product.py", line 82, in copy
    return super(product_product, self).copy(cr, uid, id, default, context)
  File "/home/openerp/openobject-addons-7.0/product/product.py", line 747, in copy
    context=context)
  File "/home/openerp/openobject-addons-7.0/mail/mail_thread.py", line 302, in copy
    return super(mail_thread, self).copy(cr, uid, id, default=default, context=context)
  File "/home/openerp/openobject-server-7.0/openerp/osv/orm.py", line 5029, in copy
    self.copy_translations(cr, uid, id, new_id, context)
  File "/home/openerp/openobject-server-7.0/openerp/osv/orm.py", line 4989, in copy_translations
    target_obj.copy_translations(cr, uid, old_child, new_child, context=context)
  File "/home/openerp/openobject-server-7.0/openerp/osv/orm.py", line 4989, in copy_translations
    target_obj.copy_translations(cr, uid, old_child, new_child, context=context)
  File "/home/openerp/openobject-server-7.0/openerp/osv/orm.py", line 4983, in copy_translations
    old_record, new_record = self.read(cr, uid, [old_id, new_id], [field_name], context=context)
ValueError: need more than 1 value to unpack

[Guewen Baconnier @ Camptocamp (gbaconnier-c2c)]

Merged Arthur Vuillard's correction in : bazaar.launchpad.net/~product-core-editors/openerp-product-attributes/7.0/revision/213